The present invention relates to cryogenic systems and, more particularly, to a multifunction cryogenic valve adapted to evacuate, seal off, and monitor vacuum levels and relieve over-pressure for cryogenic vacuum insulated systems.
Current evacuation valves for cryogenic vacuum insulated systems require additional components to make their valves function. The added components require additional space and clearance to operate; require more maintenance, spare parts, cleaning; and pose additional potential leak points and risk of breakage. The added components are needed to provide vacuum pump down, and monitoring of the vacuum, as well as an external operator and thermocouple isolation valve to evacuate and monitor the customers systems. Moreover, isolation valves require thread sealant on the thermocouple to keep the threads from leaking. Thread sealant is a concern in liquid oxygen systems because of the potential for ignition and fire. Thread sealant deteriorates after a period of time and requires replacement which makes it a maintenance requirement.
As can be seen, there is a need for a multifunction valve adapted to evacuate, seal off, monitor vacuum levels and relieve over-pressure for cryogenic vacuum insulated systems, wherein no thread sealant is necessary.